Título del libro: Stress Signaling In Plants
Título del capítulo: Signaling by microRNAs in response to abiotic stress
ALEJANDRA ALICIA COVARRUBIAS ROBLES; JOSE LUIS REYES TABOADA;
Autores externos:
Idioma:
Inglés
Año de publicación:
2013
Resumen:
In order to contend with different environmental adversities, plants have developed a series of mechanisms at the physiological, cellular and molecular level. Small RNA molecules known as microRNAs (miRNAs) are important regulators of gene expression in plants and animals. MicroRNAs are involved in plant development, response to hormones and environmental stress in plants. MicroRNAs are processed from longer RNA precursors by Dicer-like enzymes to generate 20-24 nucleotide long RNA. Within a multiprotein complex called RISC (RNA-Induced Silencing Complex), the microRNA recognizes a target mRNA by RNA:RNA base-pairing. ARGONAUTE 1 is the effector protein of the RISC complex where mRNA expression is inhibited by RNA cleavage or alternatively, by translation inhibition. How the microRNA biogenesis machinery is affected by stress conditions is only beginning to be understood. The advent of high-throughput sequencing of small RNAs has yielded a large amount of information on the miRNA landscape of many different plant species, however little is known about miRNA functions in plants other than Arabidopsis (especially crop species) and in particular their involvement in responses to external stimuli. In spite of this, many research groups have focused on how microRNAs work in relevant crops, including legumes, and their advancement may reveal novel mechanisms involved in the plant responses to different abiotic stresses. The microRNAs found in these plant species have shown novel features worth of their study: they may give rise to siRNAs (another class of non-coding small RNAs); some microRNAs accumulate to detectable levels under certain types of abiotic stress conditions or multiple small microRNAs originate from the same precursors. These findings suggest there is a wide landscape of unknown functions for microRNAs in plants. In addition, other factors should be considered to have a better and more complete picture of microRNA functions such as the half-life of the microRNA target and the microRNA itself; competition between coding and non-coding transcripts for miRNA binding; the way in which spatial, temporal and condition-specific expression of both target and microRNA is achieved; the birth of new miRNAs during evolution and their incorporation into novel regulatory pathways. Any of these factors may have a distinct contribution given particular plant situations and/or evolutionary histories. Their understanding is crucial for a full comprehension of microRNA functionality, especially in the context of abiotic stress. We have just started to uncover how microRNAs contribute to stress signaling and responses, however much remains to be learned and the near future promises great surprises that will contribute to a better understanding of the responses to abiotic stress, particularly, in crops. © Springer Science+Business Media New York 2013. All rights are reserved.
Entidades citadas de la UNAM:
ISBN:
9781461463726
Editorial:
Springer New York Nombre de la publicación:
Signaling by microRNAs in response to abiotic stress
Página inicial:
51
Página final:
67
